Lq9 427 ???
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Lq9 427 ??? This has probably been ask but I didn't find it in my search.
I have a LQ9 and was wondering about putting a 4.125 stroke crank in it. I've seen asymblies with the 4.125 stroke crank in a 3.903 bore LS1 for a 395 but none in a 6.0l block (that I can find). I was thinking maybe going with the 4.125 crank and 4.040 with the bore for a 423ci combination. Wondering if anyone has gone this route. And if so was there any clearance problems with the cam?
I have a LQ9 and was wondering about putting a 4.125 stroke crank in it. I've seen asymblies with the 4.125 stroke crank in a 3.903 bore LS1 for a 395 but none in a 6.0l block (that I can find). I was thinking maybe going with the 4.125 crank and 4.040 with the bore for a 423ci combination. Wondering if anyone has gone this route. And if so was there any clearance problems with the cam?
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From: Elmhurst, IL (Chicago Suburb)
I had a top tuner build me an iron 427 LSX motor several years ago with a 4.060 overbore and CALLLIES 4.125 crank.
DON'T DO IT based upon my miserable EXPERIENCE and I would stick with no bigger than a 4.00 inch stroke b/c my BRAND NEW CALLIES CRANK broke its crank welds and reluctor wheel (PIECE OF CRAP BRAND NEW 4.125 crank) and the motor b/f this was SUCKING AND USING OIL like a STUCK PIG.
I am sure that many builders may NOW BE ABLE to successfully build a 427 iron motor with a 4.125 crank and I can tell you I was told my builder (GUESS THE TUNER shouldn't be TUFF) told me that this stroke turned out to be too much for a 6 liter ironblock bored 4.060.
That having been said, if you feel confident with the build and you sonic check the block and have amply room to go with .060 overbore then by all means go for it and HOPE YOU HAVE BETTER LUCK than I did but I would stick with the BATTLE TESTED VENERALBE 408 iron block with 4.00 stroke and 4.030 bore and NOT GO BIGGER than 4 stroke b/c my experience was a FREAKING NIGHTMARE!!!
You can go bigger on your overbore no problem up to 4.060 if you have the meat but the GEOMEOTRY of the motor I was told by TOP TUNER was NOT RIGHT and failed.
If you to it, have a tuner that his built this exact combo and ton it MANY TIMES SUCESSFULLY as my build was the first set-up like this (IRON 427) that my tuner had done and I am sure that was a big part of the problem and this was also 4 years ago!!
DON'T DO IT based upon my miserable EXPERIENCE and I would stick with no bigger than a 4.00 inch stroke b/c my BRAND NEW CALLIES CRANK broke its crank welds and reluctor wheel (PIECE OF CRAP BRAND NEW 4.125 crank) and the motor b/f this was SUCKING AND USING OIL like a STUCK PIG.
I am sure that many builders may NOW BE ABLE to successfully build a 427 iron motor with a 4.125 crank and I can tell you I was told my builder (GUESS THE TUNER shouldn't be TUFF) told me that this stroke turned out to be too much for a 6 liter ironblock bored 4.060.
That having been said, if you feel confident with the build and you sonic check the block and have amply room to go with .060 overbore then by all means go for it and HOPE YOU HAVE BETTER LUCK than I did but I would stick with the BATTLE TESTED VENERALBE 408 iron block with 4.00 stroke and 4.030 bore and NOT GO BIGGER than 4 stroke b/c my experience was a FREAKING NIGHTMARE!!!
You can go bigger on your overbore no problem up to 4.060 if you have the meat but the GEOMEOTRY of the motor I was told by TOP TUNER was NOT RIGHT and failed.If you to it, have a tuner that his built this exact combo and ton it MANY TIMES SUCESSFULLY as my build was the first set-up like this (IRON 427) that my tuner had done and I am sure that was a big part of the problem and this was also 4 years ago!!
Last edited by MTI 427 C5 Roadster; Dec 3, 2006 at 05:06 PM.
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After reading and searching I think we will go with resleavig the block to a 4.125 bore and 4.0 strock.
Has anyone had any trouble with resleaving a 6.ol block. Is there anything I should be lookin for or know in advance?
Has anyone had any trouble with resleaving a 6.ol block. Is there anything I should be lookin for or know in advance?
